linux-mips-fnet
[Top] [All Lists]

Re: FP emulation patch available

To: "Andrew R. Baker" <andrewb@uab.edu>
Subject: Re: FP emulation patch available
From: Dominic Sweetman <dom@algor.co.uk>
Date: Tue, 14 Mar 2000 23:17:05 GMT
Cc: Ralf Baechle <ralf@oss.sgi.com>, "Kevin D. Kissell" <kevink@mips.com>, Harald Koerfgen <Harald.Koerfgen@home.ivm.de>, linux-mips@vger.rutgers.edu, linux-mips@fnet.fr, Linux SGI <linux@cthulhu.engr.sgi.com>
In-reply-to: <Pine.LNX.3.96.1000314123742.24923A-100000@lithium>
References: <20000313144657.E845@uni-koblenz.de> <Pine.LNX.3.96.1000314123742.24923A-100000@lithium>
Andrew R. Baker (andrewb@uab.edu) writes:

> ... It will also only handle operations that should produce an
> unimplemented exception (this is not quite all of the fp ops).

Denormalised operands (for example) will cause any computational
operation to blow up (change sign, load, store and move will survive -
can you think of much else?).  The requirement for MIPS hardware is
something like "you can throw an unimplemented exception in response
to any combination of operands and operation you don't like, so long
as it's rare".  That's why a complete emulator is probably a good
idea.

Dominic Sweetman
dom@algor.co.uk

<Prev in Thread] Current Thread [Next in Thread>